Why does it always rain in the UK?

Ahh, the great British weather. The subject of almost all small talk on buses, in shops, and at work – and boy do we like to complain about it. Let’s take a look at the science behind why it’s always raining in the UK, and why our weather is so unpredictable…

What causes rain?

It’s all down to the water cycle. Water evaporates from our oceans, rivers, and lakes in the form of water vapour which slowly rises into the atmosphere. At this stage, water is in its gaseous state.

This water vapour continues to rise until it reaches its dew point – this is the atmospheric temperature below which condensation occurs and water droplets begin to form (dew point varies depending on pressure and humidity). At this stage, water returns to its liquid form.

These tiny water droplets collect together as clouds, and eventually, some of those clouds will become too heavy to support their own weight – and this is when rain occurs.

The water cycle refers to this constant process of evaporation, condensation, and precipitation – and it’s vital to all life on earth.

Why Britain gets so much rain

Ocean currents are one of the most important driving forces of climate – you’ll definitely have learned about this at school, and you can refresh your memory here – it’s interesting stuff really!

The Gulf Stream is just one of those ocean currents, transporting relatively warm water from the Gulf of Mexico to the British Isles. Warm water evaporates faster than cool water, and when you consider that the UK is surrounded by sea, it becomes clear why we’re particularly prone to rain…

The UK’s location relative to ocean currents is also why our weather is so unpredictable – cold polar air from the north combined warmer tropic air causes our weather to fluctuate daily, sometimes even hourly!

But it’s not all doom and gloom

The Gulf Stream, combined with North Atlantic Drift, also gives the UK fairly mild winters.

Considering the latitude of the UK (latitude is the angular distance of a location relative to the earth’s equator), our weather should be a lot more hostile in the winter. For example, Edinburgh is at the same latitude as Moscow, yet Moscow is covered in snow all winter, with an average winter temperature of -7.5 degrees!

So next time you’re caught in the rain without a coat, don’t blame it on the weatherman…